1,273 research outputs found

    Simulating spatial variability of cereal yields from historical yield maps and satellite imagery

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    [Abstract]: The management of spatial variability of crop yields relies on the availability of affordable and accurate spatial data. Yield maps are a direct measure of the crop yields, however, costs and difficulties in collection and processing to generate yield maps results in poor availability of such data in Australia. In this study, we used historical mid-season normalised difference vegetation index (NDVI), generated from Landsat imagery over 4 years. Using linear regression model, the NDVI was compared to the actual yield map from a 257 ha paddock. The difference between actual and predicted yield showed that 77% and 93% of the paddock area had an error of <20% and <30%, respectively. The linear model obtained in the paddock was used to simulate crop yield for an adjoining paddock of 162 ha. On an average of 4 years, the difference between actual and simulated yield showed that 87% of the paddock had an error of <20%. However, this error varied from season to season. Paddock area with <20% error increased exponentially with decreasing in-crop rainfall between anthesis and crop maturity. Furthermore, the error in simulating crop yield also varied with the soil constraints. Paddock zones with high concentrations of subsoil chloride and surface soil exchangeable sodium percentage generally had higher percent of error in simulating crop yields. Satellite imagery consistently over-predicted cereal yields in areas with subsoil constraints, possibly due to chloride-induced water stress during grain filling. The simulated yield mapping methodology offers an opportunity to identify within-field spatial variability using satellite imagery as a surrogate measure of biomass. However, the ability to successfully simulate crop yields at farm scale or regional scale requires wider evaluation across different soil types and climatic conditions

    Enucleation of the solitary epithelial cyst of pancreatic head in an adult: A case report and review of the literature

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    Solitary true pancreatic cyst is a rare entity, and only a few cases are reported in the literature. We report a case of a 35&#8209;year&#8209;old woman who had a cyst in the head of the pancreas and gall stones and presented with complaints of pain in the epigastric region. The patient underwent open cholecystectomy with aspiration of the pancreatic cyst at some other private hospital. After 4 months, she presented to us with no relief in pain. Repeat contrast&#8209;enhanced computed tomography of the abdomen showed recurrence of the cyst. The patient underwent enucleation of the cyst at our hospital. During a 2&#8209;year follow&#8209;up after the enucleation, she remained asymptomatic

    Coherent manipulation of electron spins up to ambient temperatures in Cr5+^{5+}(S=1/2) doped K3_3NbO8_8

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    We report coherent spin manipulation on Cr5+^{5+} (\emph{S} = 1/2, \emph{I} = 0) doped K3_3NbO8_8, which constitutes a dilute two-level model relevant for use as a spin qubit. Rabi oscillations are observed for the first time in a spin system based on transition metal oxides up to room temperature. At liquid helium temperature the phase coherence relaxation time \emph{T2T_2} reaches ∼10\sim 10 μ\mus and, with a Rabi frequency of 20 MHz, yields a single qubit figure of merit \emph{QMQ_M} of about 500. This shows that a diluted ensemble of Cr5+^{5+} (\emph{S} = 1/2) doped K3_3NbO8_8 is a potential candidate for solid-state quantum information processing.Comment: 4 page

    Reducing the weak lensing noise for the gravitational wave Hubble diagram using the non-Gaussianity of the magnification distribution

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    Gravitational wave sources are a promising cosmological standard candle because their intrinsic luminosities are determined by fundamental physics (and are insensitive to dust extinction). They are, however, affected by weak lensing magnification due to the gravitational lensing from structures along the line of sight. This lensing is a source of uncertainty in the distance determination, even in the limit of perfect standard candle measurements. It is commonly believed that the uncertainty in the distance to an ensemble of gravitational wave sources is limited by the standard deviation of the lensing magnification distribution divided by the square root of the number of sources. Here we show that by exploiting the non-Gaussian nature of the lensing magnification distribution, we can improve this distance determination, typically by a factor of 2--3; we provide a fitting formula for the effective distance accuracy as a function of redshift for sources where the lensing noise dominates.Comment: matches PRD accepted version (expanded description of the cosmological parameter space + minor changes

    Study of operative management of proximal humerus fracture treated with locking plates

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    Background: This study was undertaken to evaluate the efficacy of Philos plate and to specifically study the clinical outcome of the patient treated with Philos plate for proximal humerus fracture on the radiological head shaft angle basis.Methods: 40 cases of proximal humerus fracture fixed by using Philos plate were reviewed.Results: Average constant shoulder score as Neer type-3 fracture is 83.8% and for type- 4 part fracture is 86%. Average radiological union was seen at 10.2 weeks. There was no major difference in clinical and radiological union. Conclusions: Good functional outcome with Philos plate irrespective of fracture type was obtained
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